Nevertheless, GSK hopes Flumoji will 'go viral', as users share the free app online and watch it spread to friends and friends-of-friends, something they can then keep track of a 'Flumoji Spreaders' leaderboard.

Hopefully the app will prove more shareable than the firm's #Flumoji hashtag, which has been used just six times on Twitter to date, with five tweets from GSK and one from an industry observer.